DE102004053272B3 - Assembly for refrigerant circuits - Google Patents

Abstract

The invention relates to an assembly for refrigerant circuits, which is arranged between the compressor and evaporator and comprises a housing with a through-channel. DOLLAR A The task is to provide an assembly for refrigerant circuits, which is designed so that it is simplified and inexpensive and can be used with less installation effort in the refrigerant circuits. DOLLAR A The solution is that within the through-channel (3, 14) a micro-channel part (4) is provided, which is designed as a functional filter-relaxation unit body, wherein in the micro-channel part (4) filtering and a relaxation of the refrigerant flowing through are simultaneously feasible.

Description

The The invention relates to an assembly for refrigerant circuits, which between an inner Heat exchanger and an evaporator is arranged and with a passageway is formed, from the high pressure side to the low pressure side directed by the refrigerant flows through is, and in the area between a connecting pipe and a Connecting piece is inserted.

The Assembly may be in the refrigerant circuits in particular of refrigerators, heat pumps and air conditioning systems, preferably used in vehicle air conditioning systems become.

Within conventional Refrigerant circuits are located in vehicle air conditioning systems on the one hand between a compressor and an evaporator at least a dirt filter and a relief valve as separate Assemblies at different points of the refrigerant circuit in the connecting pipes. there are the respective relaxation organ, a filter either locally spaced and separated or on the other hand spatially within a housing immediately preceded in order to prevent the relaxation organ with foreign bodies contaminated and / or clogged.

A locally spaced installation of the two known assemblies in a refrigerant circuit with a separator for vehicle air conditioners is in the document DE 93 03 177 U1 described, wherein in the can-shaped separation device, a filter assembly is installed, which removes foreign fluid or impurities from the coolant. The cleaned coolant is then fed to a flash valve assembly, which is physically separate from the separator, and is deflated there before being sent to the evaporator.

A spatial separation in a housing of the two modules in a refrigerant circuit with a solenoid valve disposed therein is in the document DE 100 62 666 A1 described that contains a particle filter upstream of the entry of foreign particles at its entrance during assembly in the refrigerant circuit in a housing comprising the two assemblies upstream. Particle filter and valve passage are thus arranged spatially separated from each other.

A refrigerator with two evaporators is in the document DE 195 47 744 A1 described in which a drying device with a filter assembly therein are present in front of the expansion devices, which are arranged in front of the two evaporators in the refrigerant circuit. Between the drying device and the two expansion devices is a solenoid valve for controlling the refrigerant flow in the evaporator. The expansion devices and the filter assembly are contained locally in the piping system and thus spaced from each other.

There are also cooling system components with cartridge-associated heat-relaxation valves in the document EP 1 043 553 A2 described, wherein within a provided with a pressure relief valve housing in the form of a cartridge in the upper part of the cartridge housing, the expansion valve is placed and in the lower volume region, an annular filter assembly is installed. The introduced refrigerant flows first through the filter assembly, then through a standpipe and finally to the expansion valve. This is also a spatial separation of filter and expansion valve within a housing given here.

An arrangement for controlling a Kühlkeislaufes with a Entspannungskapillarröhrchen is in the document EP 0 240 811 A1 described, in the input side, a filter assembly is connected to the pipe of the condenser, wherein the filter assembly on the output side, a longer capillary tube as relaxation relaxation followed, which is guided to the evaporator. Thus, there is a spatial succession between filter assembly and relaxation device.

A circuit for generating cold and heat with an internal heat exchanger, an evaporator, and a separate assembly therein, which contains a throttle body with a fixed flow cross-section, is in the document EP 14 29 090 A2 described, wherein the assembly is inserted directly between a connecting pipe and a connecting piece. The separate assembly can throttle, seal and filter. The associated throttle body is disc-shaped and has axially centrally a single narrow passage opening for throttling the refrigerant. On the edge sides, the module has sealing elements for edge sealing in the area of the connection pipe or the connecting piece. To filter Fremdparti angles can be assigned to the throttle body on the inlet side and / or downstream respectively mounted on the throttle body filter screens.

The assembly to which the throttle body belongs has one or two filter screens spaced apart from the throttle body. Without filter screens a fast blockage of the single narrow passage opening of the throttle body is given. Therefore, the throttle body is not at the same time a filter unit be. There is a filtering at a distance from the throttle body before and / or after the throttling of separate, different materials having components of the module.

at All mentioned arrangements of filter assemblies and expansion assemblies the two assemblies are both physically at least in consequence as well as functionally arranged one after the other separately, which high in the refrigerant circuits Costs caused.

Furthermore, a screen of sintered material for a refrigerant circuit with an internal heat exchanger - condenser -, evaporator and integrated desiccant in the document DE 203 17 084 U1 described, wherein the screen is a molded body, which consists of a cylindrical part and an adjoining tapered part. The sieve is essentially indicated as a filter. The shaped body may consist of sintered particles between which there are small channels that filter foreign particles. The sieve has consistently only one type of grain size of sintered bodies.

One Problem is that the filter screens not as throttle body are formed. In the sieve itself is explicitly no relaxation carried out.

A depth filter with a filter medium, which is produced by a rising in a radial flow direction pressure and is tubular, is in the document DE 200 06 155 U1 described. As a filter medium fleece is used, which is provided with a radially increasing pressure from outside to inside in the direction of the central region. As throttle body, this filter device can not be used.

One Problem is that the depth filter is not in refrigerant circuits as one-piece filter-relaxation body can be used is.

Of the The invention has for its object to provide an assembly for refrigerant circuits, which is designed so suitable that in a therein Material structure both throttling and filtering and refraction of Sound waves in the connected pipes, which eventually the sound transmission in the interior of vehicles should be ensured can be. Furthermore the assembly should be simplified and designed inexpensively and with less installation effort used in the refrigerant circuits can be.

The object is solved by the features of patent claim 1. In the assembly for refrigerant circuits, which is arranged between an inner heat exchanger and an evaporator and is formed with a passageway, which is directed from the high pressure side to the low pressure side flows through the refrigerant, and is used in Be rich between a connection pipe and a connecting piece , it is according to the patent claim 1 as a functional filter-relaxation unit body, wherein in the passage channel, a microchannel part containing at least two different channel widths w ₁ , w ₂ exhibiting material with microchannels as open areas in the flow cross section is present, from the high pressure side larger microchannels are present, which are followed by smaller microchannels in the direction of the low pressure side,
wherein channel widths w ₁ are located from the high-pressure-side input region and in the subsequent middle region of the microchannel part, so that on average a predetermined flow cross-section is present,
wherein in a subsequent transition zone between the central region and an output region, the channel widths w _{1 are} traversed by smaller channel widths w ₂ , so that on average reduces the local flow cross-section, and
wherein in a low-pressure-side outlet region, the smaller channel widths w ₂ are present, which on average form the smallest flow cross-section,
wherein there is a small pressure loss with Δp << Δp _ges in the input range, which is almost constant up to the transition zone with Δp> 0, wherein the pressure loss increases significantly with Δp = Δp _ges only in the output range.

The Micro-channel part is with its filter characteristic for mounting of Foreign components in the entrance area at existing free intermediate areas of microchannels as well as having a relaxing property in the exit area rejuvenating microchannels Mistake.

One for one Relaxation filter performance given flow volume of the microchannel part may be due to size, thickness of the microchannel part and size of the inner Defined components of the material.

Of the Through-channel has two pass holes, the one input-side fitting hole and an output-side fitting hole represent, wherein the inner diameter of the input-side pass hole the outer diameter corresponds to the plug-in connection pipe.

The microchannel part is introduced in an annular support part, which is approximately in the central region of the through-channel in the Ausgangsssessei tiger fitting hole arranged and can be fastened from the outside by means of a screw.

The Holder part can be used as a screw-in hexagon socket screw be formed, in which the micro-channel part is located, wherein the output side fitting hole is threaded and the hexagon recess for the refrigerant continuously is.

The input-side fitting hole preferably has an inner diameter, the outside diameter corresponds to the inserted connection pipe.

Between the output-side fitting hole and the input-side fitting hole can be an annular, the passage channel narrowing channel collar as arrangement area be present, at which the support member with the micro-channel part therein strikes and is fixed.

The the microchannel part containing support member may be exchangeable Holder part be formed.

At the channel collar at the end of the input-side pass hole can strike the inserted connection pipe.

in the Through-channel can replace the channel collar one the input side Passhole widening, single-stage heel be present at the the micro-channel part attached edge area side and fixed there is.

The Microchannel part may vary depending on the size of the passageway as a cylinder body, Disc or tablet be formed.

The Micro-channel part can be used as internal components porous materials, in particular sintered metal body continuously exhibit.

The Micro-channel part can be made as a fully cylindrical single body payout like Structure formed be, wherein in an entrance area are first metal body, between those on average over a cross-sectional area a predetermined flow cross section is defined, wherein in a subsequent middle area, the first Metal body available are, their first cross-sectional area a flow cross-section approximately corresponds to that of the input area, optionally in a subsequent transition zone between the central area and an exit area the first grain larger metal body of second grain smaller metal bodies are interspersed, so that on average the local flow cross-section decreases, and wherein in an exit region, the second metal body present are the lowest in the second cross-sectional area Form flow cross section.

The channel-rejuvenating and pour-like structure of the microchannel part breaks the sound waves in the pipes and dampens while the sound transmission in the interior of the passenger compartment.

The Assembly can be designed like a cartridge.

The Invention will be described with reference to several embodiments by means of several Drawings explained in more detail.

It demonstrate:

1 a schematic representation of a first assembly according to the invention for a refrigerant circuit in longitudinal section with interchangeable micro-channel part and

2 a schematic representation of a second assembly according to the invention for a refrigerant circuit in longitudinal section with firmly introduced micro-channel part and

3 an enlarged longitudinal section ( 3a ), two enlarged cross sections ( 3b . 3c ) through the microchannel part with different sizes of the internal components and a schematic representation ( 3d ) of the pressure loss Δp over the length L of the microchannel part in the flow direction of the refrigerant.

In 1 is a first assembly 1 for a refrigerant circuit disposed between the compressor and evaporator and a housing 2 with a passageway 3 includes.

The assembly 1 Contains in the passageway 3 a microchannel part 4 formed as a functional filter-relaxation unit body and at an area inside the passageway 3 is introduced, wherein in the micro-channel part 4 a filtering and a relaxation of the refrigerant flowing through are parallel at the same time feasible.

The microchannel part 4 with the filter property on the one hand is for holding foreign components 24 at existing free intermediate areas of microchannels 5 . 5 ' given. The microchannel part 4 with the relaxation property on the other hand is by micro-channel-sized constrictions, averaged over all cross-sectional INTRAN dene and longitudinally tapered microchannels 5 ' . 5 '' , given.

• – Festhalten der Fremdbestandteile 24 des einströmenden Kältemittels an Wandungen und den freien Zwischenbereichen der Mikrokanäle 5, 5' und
• – Drosseln der Strömungsgeschwindigkeit des Kältemittels von der Hochdruckseite des Verdichters aus zur Niederdruckseite des Verdampfers gerichtet in den sich verjüngenden Mikrokanälen 5', 5''.

The in the micro-channel part 4 existing numerous microchannels 5 . 5 ' . 5 '' thus have a double function:

• - Holding the foreign components 24 the inflowing refrigerant on walls and the free intermediate areas of the microchannels 5 . 5 ' and
• - Restricting the flow rate of the refrigerant from the high pressure side of the compressor from the low pressure side of the evaporator directed in the tapered microchannels 5 ' . 5 '' ,

The passageway 3 preferably has two pass holes 9 . 7 on, the input-side fitting hole 9 and a first output-side fitting hole 7 represent, wherein the inner diameter of the input-side pass hole 9 preferably the outer diameter of the insertable tube 10 on the compressor side.

In 1 is the microchannel part 4 in an annular support part 6 introduced, approximately in the central area of the passageway 3 in a first output pass hole 7 is arranged and can be fixed from the outside by means of a screw.

The mounting part 6 can in particular as a externally preferably operable with a hexagon socket screw with preferably a hexagon recess 20 be formed, wherein the first output-side fitting hole 7 with a thread 8th is provided, in which the mounting part 6 is firmly screwed.

Through the screwable mounting part 6 It can itself as an exchangeable support part with the micro-channel part 4 be educated.

Between the first exit-side pass hole 7 and the input-side pass hole 9 can be an annular, the passageway 3 narrowing canal cuff 19 be present as an inner arrangement area, on the part of the first exit-side pass hole 7 the mounting part 6 with the microchannel part inside 4 strikes and is fixable.

The opposite side of the channel cuff 19 is the end portion of the input-side fitting hole 9 , wherein the inserted connection pipe 10 at the channel cuff 19 can strike.

The connection pipe 10 the compressor can in the input-side fitting hole 9 be stably locked by a soldering.

As connection of the evaporator to the module 1 is a connecting piece 11 with a flange 12 provided, which serves for holding directly on the evaporator or on its supply pipe (not shown).

The housing 2 the assembly 1 may in a variation of the housing as a connection block with a through-channel 3 be arranged for connecting pipes and / or components in the piping system of compressor and evaporator of the refrigerant circuit.

In a second embodiment, as in 2 is shown, the second assembly according to the invention 13 a second passageway 14 in which between a second output-side fitting hole 15 and the input-side pass hole 9 a single-stage, channel-increasing sales 16 is present at which the microchannel part 4 from the side of the entrance-side pass hole 9 is attached and can be fixed.

As an additional support for the microchannel part 4 at this paragraph 16 This can be done in the input-side fitting hole 9 inserted connection pipe 10 serve, which is also on the sewer wall 17 and the housing 2 is stable solderable.

The refrigerant also flows here as in the first module 1 in the flow direction 18 directed from the high pressure side of the compressor to the low pressure side of the evaporator in the refrigerant circuit.

The microchannel part 4 is thus generally in the passageway 14 firmly locked.

The microchannel part 4 may vary depending on the size of the passageway 14 be designed as a solid cylinder, disc or tablet.

The associated flow volume of the microchannel part 4 to adjust the filter relaxation performance may optionally by size, thickness of the micro-channel part 4 and size of the internal components of the material. In this case, the micro-channel part 4 as inner constituents mesh or hole materials in which different mesh sizes or hole pattern can be realized. In particular, the mesh size w in the flow direction 18 from w1 to w2 downsize, leaving in the area of the microchannel part 4 in a holistic bond a combined functional filter-relaxation characteristic occurs.

The microchannel part 4 can also have as internal components porous materials, in particular sintered metal body throughout.

In another embodiment of the assembly according to the invention, for example, the micro-channel part 4 consist of compressed grain layers with different microchannels as open areas in the flow cross section, from the high pressure side (compressor side) of larger microchannels 5 ' , as in 1 is shown, which are in the direction of the low pressure side (evaporator side) microchannels 5 '' followed by smaller holes or meshes in the form of smaller porosities.

The assemblies 1 and 13 can be a case 2 not only in the form of a connecting block, but may also be formed in the form of a circular universal and cartridge-like assembly.

In a further embodiment with dimensions is in 3 the operation of a micro-channel part according to the invention 4 in a longitudinal section ( 3a ) and in two cross sections ( 3b . 3c ) explained in more detail. In the 3 are the microchannels 5 . 5 ' . 5 '' with different channel width w available, with in the flow direction 18 Input range side microchannels 5 . 5 ' with larger channel width w1 and output range side microchannels 5 '' are provided with smaller channel width w2.

In 3a is the microchannel part 4 shown in a more detailed longitudinal section, as a cylindrical single body 21 is formed in pour-like structural form.

In the entrance area 22 are first sintered metal body 23 , between which a predetermined flow cross-section is defined on average over a cross-sectional area. In the entrance area 22 can be a deposit of foreign components 24 that contaminate the refrigerant take place.

In the middle area 25 are predominantly the first metal bodies 23 present, their first cross-sectional area 29 a flow cross-section approximately that of the input area 22 equivalent.

In a subsequent transition zone 26 between the middle area 25 and an exit area 27 can be the first grain larger metal body 23 second grain smaller sintered metal bodies 28 be interspersed, so that reduced on average the local flow cross-section.

In the exit area 27 are almost invariably only the second metal body 28 present in the second cross-sectional area 30 on average the smallest flow cross-section, as in 3b shown, train. Here, too, is a pour-like structural form of the second grain smaller metal body 28 available.

Here is the entrance area 22 larger mesh than the exit area 27 trained, as in the 3b and 3c is shown.

Thus, the mesh width w1 as a channel width is on average above the first cross-sectional area 29 ( 3c ) with respect to the mesh width w2 on the average over the second cross-sectional area 30 ( 3b ) of the cylindrical body 21 much bigger.

The dividend similar structure is e.g. typical for sintered metal body.

Porous material, such as sintered metal in bulk-like structural form can therefore be used because it is particularly able to reduce the pressure from a high pressure side to a low pressure side in a refrigerant circuit and at the same time foreign components 24 to filter out of the refrigerant.

Due to the predetermined length of the solid cylinder over the longitudinal section on the existing taper of the microchannels of 5 . 5 ' to 5 '' Thus, in addition to the initial filtering and a relaxation of the refrigerant is brought about.

In 3d is the course of the pressure drop Δp in the microchannel part 4 over the length L of the cylinder body 21 specified. In the entrance area 22 is a very small and slightly increasing pressure drop due to the binding of foreign components 24 to be recorded with Δp << 1. in the middle range 25 remains due to the largely remaining original flow cross-section of the pressure drop Δp largely at the same level. Only in the transition zone 26 and subsequently especially in the exit area 27 the pressure drop Δp increases rapidly according to the intended refrigerant relaxation.

The module according to the invention 1 can with the following dimensions for the micro-channel part 4 be of the following order of magnitude:
For example, for a vehicle air conditioning:
Diameter of the solid cylinder approx. 2-20mm, preferably 4mm;
Length about 2 to 20 mm, preferably 3mm;
Filter classes between 1μm to 100μm, preferably 1μm.

For others Applications can other dimensions and dimensions may be required to complete the set predetermined refrigerant flows and pressure differences Δp to be able to.

The invention opens up the possibility that in addition to the combination of the two filter-relaxation properties within a body 21 of the specified microchannel part 4 with the microcanals len 5 . 5 ' . 5 '' as a third property, a reduction of the flow noise in the refrigerant circuit can be brought about. The channel-tapering bulk-like structure can break the sound waves in the pipelines and thereby dampen the transmission of sound into the interior of the passenger compartment. The module according to the invention 1 respectively. 13 thus represents simultaneously a sound reduction device.

The invention also makes it possible to reduce the number of maintenance intervals due to the contamination of the entrance area 22 to reduce, with the entrance area 22 and the middle area 25 with the first grain-sized metal bodies 23 and larger flow area avoid it, a possible throttling effect already in the two areas 22 . 25 due to contamination by the foreign particles 24 let develop.

The inventive module is universal for all refrigerant circuits can be used.

1

first module

2

casing

3

first Through channel

4

Microchannel portion

5

microchannels

5 '

larger microchannels

5 ''

smaller microchannels

6

supporting member

7

first Output-side pass hole

8th

thread

9

input side fitting hole

10

connecting pipe

11

spigot

12

flange

13

second module

14

second Through channel

15

second output pass hole

16

gradual paragraph

17

inner wall the third pass hole

18

flow direction of the refrigerant

19

channel cuff

20

Hexagon socket recess

21

solid-cylindrical body

22

entrance area

23

First metal body

24

Impurities

25

the central region

26

Transition zone

27

output range

28

Second metal body

29

First Cross sectional area

30

Second Cross sectional area

L

Length of the Microchannel part

Ap

pressure drop in the microchannel part

w

Channel / mesh

w1

large mesh size

w2

small mesh

Claims (16)

Assembly for refrigerant circuits, which is arranged between an inner heat exchanger and an evaporator and is formed with a passage channel, which is directed from the high pressure side to the low pressure side flows through the refrigerant, and which is inserted in the region between a connecting pipe and a connecting piece, characterized in that it is designed as a functional filter-relaxation unit body, wherein in the through-channel ( 3 . 14 ) a microchannel part ( 4 ), comprising at least two different channel widths w ₁ , w ₂ exhibiting material ( 23 . 28 ), with microchannels ( 5 . 5 ' . 5 '' ) is present as free regions in the flow cross-section, with larger microchannels directed from the high-pressure side ( 5 . 5 ' ), which have smaller microchannels ( 5 '' ), with the high-pressure-side input area ( 22 ) from and in the following middle range ( 25 ) of the microchannel part ( 4 ) Channel width w ₁ , so that on average a predetermined flow cross-section is present, wherein in a subsequent transition zone ( 26 ) between the middle area ( 25 ) and an exit area ( 27 ) the channel widths w _{1 are} traversed by smaller channel widths w ₂ , so that on average the local flow cross-section decreases there, and wherein in a low-pressure-side output region ( 27 ), the smaller channel widths w ₂ are present, which on average form the smallest flow cross-section, with a low pressure loss with Δp << Δp _ges in the input region (FIG. 22 ), which reaches the transition zone ( 26 ) with Δp> 0 is almost constant, the pressure loss with Δp = Δp _ges only in the output range ( 27 ) increases significantly. An assembly according to claim 1, characterized in that the microchannel part ( 4 ) with its filter property for holding impurities ( 24 ) in the entrance area ( 22 ) at existing free intermediate areas of microchannels ( 5 . 5 ' ) and with a relaxation property in the exit area ( 27 ) by tapered microchannels ( 5 ' . 5 '' ) is provided. An assembly according to claim 1 or 2, characterized in that a predetermined for a relaxation filter performance flow volume of the microchannel part ( 4 ) by size, thickness of the microchannel part ( 4 ) and size of internal components ( 23 . 28 . 5 . 5 ' . 5 '' ) of the material is defined. An assembly according to claim 1, characterized in that the passageway ( 3 ) two pass holes ( 9 . 7 ) having an input-side fitting hole ( 9 ) and an output-side fitting hole ( 7 ), wherein the inner diameter of the input-side pass hole ( 9 ) the outer diameter of the plug-in connection tube ( 10 ) corresponds. Assembly according to claim 4, characterized in that the microchannel part ( 4 ) in an annular support part ( 6 ), which is approximately in the central region of the through-channel ( 3 ) in the exit-side fitting hole ( 7 ) is arranged and fastened from the outside by means of a screw. An assembly according to claim 5, characterized in that the mounting part ( 6 ) is formed as an externally screwed hexagon socket screw, in which the micro-channel part ( 4 ), wherein the output-side fitting hole ( 7 ) with a thread ( 8th ) and the hexagon recess ( 20 ) is continuous for the refrigerant. An assembly according to claim 4, characterized in that the input-side fitting hole ( 9 ) has an inner diameter which corresponds to the outer diameter of the inserted connecting pipe ( 10 ) corresponds. An assembly according to claims 6 and 7, characterized in that between the output side fitting hole ( 7 ) and the input-side fitting hole ( 9 ) an annular, the passageway ( 3 ) narrowing channel cuff ( 19 ) is present as an arrangement area at which the mounting part ( 6 ) with the microchannel part ( 4 ) strikes and is fixed. An assembly according to claim 8, characterized in that the microchannel part ( 4 ) containing support part ( 6 ) is designed as an exchangeable mounting part. An assembly according to claim 8, characterized in that at the channel sleeve ( 19 ) at the end region of the input-side pass hole ( 9 ) the inserted connection pipe ( 10 ) strikes. Assembly according to Claims 1 and 8, characterized in that in the passageway ( 14 ) instead of the channel sleeve ( 19 ) a the input-side fitting hole ( 9 ) expanding one-step paragraph ( 16 ) at which the microchannel part ( 4 ) is attached on the edge area side and fixed there. An assembly according to claim 1, characterized in that the microchannel part ( 4 ) depending on the size of the through-channel ( 3 . 14 ) is designed as a cylinder body, disc or tablet. An assembly according to claim 3, characterized in that the microchannel part ( 4 ) as inner constituents porous materials, in particular sintered metal bodies ( 23 . 28 ) consistently. An assembly according to claim 13, characterized in that the microchannel part ( 4 ) as a fully cylindrical single body ( 21 ) is formed of bulk-like structure, wherein in an entrance area ( 22 ) first metal body ( 23 ), between which a predetermined flow cross-section is defined on average over a cross-sectional area, wherein in a subsequent central area ( 25 ) the first metal bodies ( 23 ) whose first cross-sectional area ( 29 ) a flow cross-section approximately that of the input area ( 22 ), optionally in a subsequent transition zone ( 26 ) between the middle area ( 25 ) and an exit area ( 27 ) the first grain-sized metal bodies ( 23 ) of second grain smaller metal bodies ( 28 ) are interspersed, so that on average reduces the local flow cross-section, and wherein in an output region ( 27 ) the second metal bodies ( 28 ) which are in the second cross-sectional area ( 30 ) form on average the smallest flow cross-section. An assembly according to claim 14, characterized in that the channel-tapering and bulk-like structure of the microchannel part ( 4 ) Breaks the sound waves in the pipes and thereby dampens the sound transmission into the interior of the passenger compartment. Assembly according to the preceding claims, characterized characterized in that it is designed like a cartridge.